Bryon Jacob and Chris Berry: "AtomServer is an off-the-shelf implementation of an Atom Store. It is implemented as a Java web application, and should deploy into any J2EE Servlet Container. Under the covers, AtomServer uses the Apache Project’s open-source implementation of the Atom Protocol, called Abdera, to process the RESTful verbs and XML vocabulary of Atom."
It looks AtomServer captures a number of idioms and patterns for handling "non-html" content. It'll be interesting to see if any of the major Java frameworks plunder these approaches - I hope they do. The next thing is figuring out systems and data patterns for handling traffic. The target figure of 1M hits per day might not be enough to stress out classic 3 tiered solutions or features that hurt relational databases, like tagging and social graphs.